Measuring system of absorbed dose standard for electron beam radiation processing

The design and experiments of an absorbed dose calorimeter in quasi-adiabatic mode of operation and its measuring system were described. The absorption disk and outer shell of the calorimeter were made of anisotropic pyrolytic graphite. The graphite itself was used as heating resistor of the electrical heating unit, for the purpose of check and simulation. The ratio of calculated value and experimental one for temperature rising is 1.008. The standard deviation is less than 0.6%. The total uncertainty of absorbed dose determination with the graphite calorimeter approximates to 2.7% (K=2) for the 0.5-3.0 MeV electron beam in the dose range of 1-5×102kGy. the powder alanine/ESR dosimeter and plastic thin-film dosimeter can be calibrated by the calorimeter. The passivation of temperature rising curve, heat equilibrium, measurement of calorimetric ratio and its error were also discussed.